ADSORPTION OF LOW-DENSITY LIPOPROTEINS ONTO SELECTED BIOMEDICAL POLYMERS

This study examines the interaction of human low density lipoprotein (LDL) with a select group of biomedical polymers. The adsorption characteristics of LDL on cured filler-free poly(dimethyl Siloxane) (C-PDMS), Biomer, Cardiomat 610, Kraton 1650, poly(hydroxyethyl methacrylate) (PHEMA) and glass are presented. Adsorption of LDL to charged hydrophilic glass control surfaces occurred rapidly, reaching plateau concentrations within one minute (0. 19 plus or minus 0. 01 ug/cm**2). Adsorption of LDL to polymer surfaces appeared to be dependent upon both the polymer hydrophobicity (or apolar nature), and flexibility (or dynamic nature) at the interface. Increased surface concentrations were observed for Biomer (0. 32 plus or minus 0. 01 ug/cm**2) as well as other polymers which exhibited both hydrophobic and elastomeric properties. LDL adsorption is dependent upon polymer hydrophobicity, flexibility and temperature. Competitive adsorption experiments suggests that LDL may have a substantial influence on protein adsorption.